Tube pump, tube for tube pump and liquid ejecting apparatus

ABSTRACT

A tube pump, includes a tube, a tube pump body including a roller, and rotating the roller for depressing to flatten the tube, and a pump holder, having substantially a cylindrical shape, and containing the tube pump body and the tube therein. The tube has a curve portion, an upstream side portion extended upstream from the curve portion, and a downstream side portion extended downstream from the curve portion. The tube is drawn out so as to overlap the upstream side portion and the downstream side portion being parallel each other. Also, a second tube pump includes a tube, a casing containing a flow path middle portion of the tube, and a pressing member pressing the flow path middle portion against an inner wall of the casing. The pressing member includes a contact member facing to the casing through the tube and an urging member urging the contact member to the tube by an elastic force. Also, a tube for a tube pump includes a plurality of tube bodies, each including a flow path, and a tube connecting portion connecting the tube bodies separately from each other so as to escape wall thicknesses of the tube bodies in a state that the tube is depressed to flatten.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a tube pump, a tube for the tube pump and a liquid ejecting apparatus.

[0002] In a related art, by depressing to flatten a tube by a tube pump main body from an upstream side to a downstream side of the tube, the tube pump transports an ink fluid in the tube which is depressed to flatten to downstream. Here, there is a case of using a plurality of tubes to increase a flow rate of the tubes. Further, there is a tube in which outer peripheries of a plurality of tube main bodies are connected directly with an object of facilitating an operation of assembling the tube (for example, refer to JP-A-2001-193670).

[0003] However, in the case of the tube connecting the plurality of tube main bodies, when the tube pump depresses to flatten the tube, the contiguous tube main bodies are deformed to push each other. Thereby, a load necessary for depressing to flatten the tube becomes larger than a load in the case of depressing to flatten a single one of the plurality of tube main bodies multiplied by a number of pieces of the tube main bodies to thereby pose a problem that torque for driving the tube pump is increased and a motor for driving the tube pump becomes large-sized.

[0004] Also, a length of the tube contained in the pump holder is adjusted by visual observation after the tube has been arranged to be along the inner wall of the pump holder. Therefore, there is a case in which the length of the tube is not adjusted optimally.

[0005] Further, an ink jet printer has widely been used as a related liquid ejecting apparatus for ejecting a liquid to a target via a liquid ejecting head. Further, in such an ink jet printer, at a recording head as a liquid ejecting head, there is a concern that printing is not carried out excellently since ink at a vicinity of a nozzle becomes viscous or bubbles are mixed into the nozzle. Hence, there have been proposed a number of head cleaning mechanisms for recovering the liquid ejecting head.

[0006] There is known a head cleaning mechanism for covering the nozzle of the recording head by a cap, driving a pump provided in an ink discharge path communicated with the cap and sucking ink from the nozzle by utilizing pressure (negative pressure) generated by a pump.

[0007] Further, as one of the pumps, a second related tube pump 101 as shown in FIG. 19 is known. The tube pump 101 includes a flexible tube 103 provided in a shape of a circular arc along a casing 102, a roller 104 for pressing the flexible tube 103 and a rotating member 105 for supporting the roller 105. That is, the flexible tub 103 is arranged substantially over a half periphery of the casing 102 along an inner wall of the casing 102. Further, by rotating the rotating member 105, the roller 104 is moved while successively depressing to flatten the flexible tube 103, thereby, pressure in the flexible tube 103 upstream from a portion thereof contained in the casing 102 is reduced.

[0008] Further, when the tube pump 101 is provided with only one of the roller 104, in accordance with rotation of the rotating member 105, a state in which the roller 104 depresses to flatten the flexible tube 103 and a state in which the roller 104 does not depress to flatten the flexible tube 103 are repeated. Therefore, when the flexible tube 103 is not depressed to flatten the roller 104, upstream and downstream thereof are brought into a communicating state and there is a possibility that negative pressure accumulated on the upstream side is extinguished. As a result, generation of pressure is intermittent, accumulation of pressure is difficult and there is a concern that pertinent negative pressure cannot be generated at inside of the cap.

[0009] Hence, there is a constitution in which the rotating member 105 is provided with two or more of the rollers 104 and when the rotating member 105 is rotated, at least one of the rollers 104 is necessarily depressed to flatten the flexible tube 103 to thereby enable to accumulate the negative pressure. However, by providing two or more of the rollers 104, there poses a problem that the apparatus is complicated and cost is increased.

[0010] Hence, as shown in FIG. 20, there is proposed the tube pump 101 provided with the flexible tube 103 intersected by 360° or more, that is, in a shape of a along the casing 102 (for example, refer to JP-A-2001-301195). Further, thereby, the flexible tube 103 includes an overlapped portion 107 and even when there is only one of the roller 104, the roller 104 can always depress to flatten the flexible tube 103. As a result, the upstream side of the tube pump 101 is not opened intermittently to the downstream side and negative pressure can be continuously accumulated to the upstream side.

[0011] However, since the tube pump 101 of the related art includes the overlapped portion 107, there poses a problem that a space in a direction along a rotating shaft is increased.

SUMMARY OF THE INVENTION

[0012] It is therefore an object of the present invention to provide a tube for a tube pump capable of downsizing a motor for driving the tube pump, a tube pump capable of adjusting a length of a tube used in the tube pump optimally, and a tube pump and a liquid ejecting apparatus capable of simplifying and downsizing structure of apparatus. The object is achieved by a combination of characteristics described in independent claims in the scope of claims. Further, dependent claims prescribe a further advantageous specific example of the invention.

[0013] In order to achieve the above object, according to the present invention, there is provided a tube for a tube pump, comprising:

[0014] a plurality of tube bodies, each including a flow path; and

[0015] a tube connecting portion, connecting the tube bodies separately from each other so as to escape wall thicknesses of the tube bodies in a state that the tube is depressed to flatten.

[0016] Thereby, a load necessary for depressing to flatten the tube can be reduced in comparison with that of the case of directly connecting outer peripheries of the plurality of tube main bodies and the tube pump can be downsized.

[0017] Preferably, the tube is depressed to flatten by a load given by multiplying a load for depressing a single tube body of the tube bodies to flatten by substantially a number of the tube bodies of the tube. In the above configuration, a total of the tube can be depressed to flatten by a total of loads of depressing to flatten the individual tubes.

[0018] Preferably, the tube includes at least two tube bodies connected by the tube connecting portion. A diameter of each of the tube bodies is 4.6 mm, a wall thickness thereof is 1 mm, and a distance between centers of adjacent tube bodies of the at least two tube bodies is 5.1 mm. In the above configuration, the tube can sufficiently be depressed to flatten even when the load of depressing to flatten the tube for the tube pump is substantially twice as much as a load when one of the tube main bodies is depressed to flatten.

[0019] Preferably, the tube connecting portion separates the tube bodies from each other in a state that the tube is not depressed to flatten. The tube makes the tube bodies proximate to each other in a state that the tube is depressed to flatten. Thereby, the tube pump can be downsized within a range in which the contiguous tube main bodies are not deformed to push each other.

[0020] Here, it is preferable that, the tube connecting portion is buckled so as to make the tube bodies proximate to each other when the tube is depressed to flatten. Thereby, it is reduced that the tube for the tube pump becomes difficult to be depressed to flatten by the tube connecting portion.

[0021] Preferably, the tube connecting portion connects the tube bodies substantially at a center of the tube bodies in a direction of depressing the tube bodies to flatten. Thereby, the respective tube main bodies connected to the tube connecting portion are uniformly depressed to flatten.

[0022] According to the present invention, there is also provided A tube pump, comprising:

[0023] a tube, drawn out in a shape of a ring;

[0024] a tube pump body, including a roller, and rotating the roller for depressing to flatten the tube from an inner side of the ring;

[0025] a pump holder, having substantially a cylindrical shape, and containing the tube pump body and the tube therein; and

[0026] a tube holder, detachably mounted on the pump holder, and holding the tube in the shape of the ring as a ring portion by overlapping an upstream side portion extended upstream from the ring portion of the tube and a downstream side portion extended downstream from the ring portion of the tube.

[0027] In the above configuration, a length of the ring portion of the tube can previously be adjusted before the tube is arranged to be along an inner wall of the pump holder. Therefore, the length of the ring portion of the tube is made to be easy to adjust optimally.

[0028] Preferably, the tube holder is detachably mounted on the pump holder in a direction intersecting with the ring portion of the tube. Thereby, the tube becomes easy to integrate to the pump holder.

[0029] Preferably, the tube includes a plurality of tube bodies. The tube holder includes a positioning projection projected along a longitudinal direction of the tube bodies for positioning the tube bodies. Thereby, the plurality of tube bodies can firmly be positioned to the tube holder.

[0030] Preferably, the tube holder holds the tube in a state of bending the tube. Thereby, the tube is difficult to draw from the tube holder even when the tube is subjected to a pulling force.

[0031] Preferably, the tube holder includes a tube holder body and a tube holder lid. The tube holder body and the tube holder lid holds the tube at a clearance therebetween. The clearance is smaller than an outer diameter of the tube in a sate that the tube holder is attached to the pump holder. Therefore, even when a force of fitting the tube holder main body and the tube holder lid is small, the tube is firmly held by the pump holder along with the tube holder.

[0032] According to the present invention, there is also provided a tube pump, comprising:

[0033] a tube;

[0034] a tube pump body, including a roller, and rotating the roller for depressing to flatten the tube; and

[0035] a pump holder, having substantially a cylindrical shape, and containing the tube pump body and the tube therein,

[0036] wherein the tube has a curve portion, an upstream side portion extended upstream from the curve portion, and a downstream side portion extended downstream from the curve portion; and

[0037] wherein the tube is drawn out from the tube pump body so as to overlap the upstream side portion and the downstream side portion being parallel each other.

[0038] According to the present invention, there is also provided a tube pump, comprising

[0039] a tube;

[0040] a casing, containing a flow path middle portion of the tube; and

[0041] a pressing member, pressing the flow path middle portion against an inner wall of the casing,

[0042] wherein the pressing member includes:

[0043] a contact member, facing to the casing through the tube; and

[0044] an urging member, urging the contact member to the tube by an elastic force.

[0045] Preferably, the flow path middle portion is contained along the inner wall of the casing so as to draw in a Ω shape. The tube has a bundled portion in which an upstream side end portion and a downstream side end portion of the flow path middle portion are overlapped in a state that directions of liquid flow in the upstream side end portion and the downstream side end portion are reverse to each other.

[0046] In the above configuration, the flow path middle portion of the flexible tube is arranged in the casing to draw the character Ω shape and therefore, the flexible tube is not provided with an overlapped portion formed when, for example, the flexible tube is intersected in an α-like shape. As a result, an extra space for the overlapped portion needs not to ensure and the tube pump can be downsized. Further, the contact member presses the flexible tube by the elastic force by the urging memver and therefore, the flexible tube is flexibly pressed by the contact member. As a result, even the flexible tube disposed at the bundled portion and the flexible tube disposed at other portion can similarly be depressed to flatten. Therefore, the upstream side end portion and the downstream side end portion can simultaneously be depressed to flatten. As a result, even when the flow path middle portion of the flexible tube is constituted in the Ω-like shape and is not provided with the overlapped portion, some portion of the flexible tube can always be depressed to flatten by the single contact member and pressure can be accumulated continuously in the flexible tube by a simple constitution. Further, pressure can be accumulated in a shorter period of time than in the case of accumulating pressure discontinuously.

[0047] Preferably, the inner wall of the casing is formed in a cylindrical shape. The urging member includes a rotating member, rotated with a center of the inner wall as an axis center, a supporting member, supported on the rotating member so that a distance of the contact member from the axis center can be changed, and supporting the contact member, an elastic member, disposed between the rotating member and the supporting member, and urging the supporting member by the elastic force such that the contact member is separated from the axis center.

[0048] In the above configuration, the casing is formed in the cylindrical shape, the urging member is constituted by three members of the rotating member, the supporting member and the elastic member and therefore, the constitution of the tube pump can be simplified. Further, pressure of the tube pump can smoothly be accumulated despite the simple constitution.

[0049] Preferably, the supporting member is supported on the rotating member such that a position of the contact member can be changed between a first position and a second position. The first position is capable of pressing the bundled portion so that the upstream side end portion and the downstream side end portion are simultaneously depressed to flatten. The second position is capable of depressing to flatten the flow path middle portion between the upstream side end portion and the downstream side end portion.

[0050] In the above configuration, even when the flow path middle portion of the tube is constituted by the Ω-like portion and is not provided with the overlapped portion, some portion of the flexible tube can always be depressed to flatten by the single contact member and pressure can be accumulated continuously in the flexible tube by a simple constitution. Further, pressure can be accumulated in a shorter period of time than in the case of accumulating pressure discontinuously.

[0051] Preferably, the tube includes a plurality of tubes. Particularly, a plurality of the flexible tubes are provided to single ones of the casing and the pressing member.

[0052] In the above configuration, since the plurality of flexible tubes are provided, a sucking function of the tube pump can be increased. Further, even when the plurality of flexible tubes are provided, the flexible tube is not provided with the overlapped portion and therefore, even when two pieces of the flexible tubes are used to increase the sucking function, a space of containing two pieces of the flexible tubes may be provided in the casing and the space is saved.

[0053] Preferably, the tubes has a tube connecting portion which connects adjacent tubes of the tubes.

[0054] In the above configuration, the plurality of tubes are connected to constitute one aggregation and therefore, the plurality of tubes are easy to deal with and operation of integrating the flexible tubes to the tube pump is facilitated.

[0055] Preferably, only a single one of the contact member is provided on the supporting member.

[0056] In the above configuration, only one of the contact member is provided and therefore, the structure can be simplified. Further, even when only one of the contact member is provided, the upstream side end portion and the downstream side end portion can simultaneously be depressed to flatten and even when the flow path middle portion of the flexible tube is not provided with the overlapped portion, some portion of the flexible tube can always be depressed to flatten by the single contact member and pressure can be accumulated continuously in the flexible tube.

[0057] According to the present invention, there is also provided a liquid ejecting apparatus, comprising:

[0058] a tube pump, including:

[0059] a tube;

[0060] a casing, containing a flow path middle portion of the tube; and

[0061] a pressing member, pressing the flow path middle portion against an inner wall of the casing,

[0062] wherein the pressing member includes:

[0063] a contact member, facing to the casing through the tube; and

[0064] an urging member, urging the contact member to the tube by an elastic force.

[0065] Preferably, flow path middle portion is contained along the inner wall of the casing so as to draw in a 0 shape. The tube has a bundled portion in which an upstream side end portion and a downstream side end portion of the flow path middle portion are overlapped in a state that directions of liquid flow in the upstream side end portion and the downstream side end portion are reverse to each other.

[0066] In the above configuration, the flow path middle portion of the tube is arranged in the casing to draw in the Ω shape and therefore, the tube is not provided with the overlapped portion formed when, for example, the tube is intersected in an α-like shape. As a result, an extra space for the overlapped portion needs not ensure and downsizing of the tube pump and downsizing of the liquid injecting apparatus can be achieved. Further, since the contact member presses the flexible tube by the elastic force by the urging member, the flexible tube is flexibly pressed by the contact member. As a result, even the flexible tube disposed at the bundled portion and the flexible tube disposed at other portion can similarly be depressed to flatten. Therefore, the upstream side end portion and the downstream side end portion can simultaneously be depressed to flatten. As a result, even when the flow path middle portion of the flexible tube is constituted by the Ω-like shape and is not provided with the overlapped portion, some portion of the flexible tube can always be depressed to flatten by the single contact member and pressure can be accumulated continuously in the flexible tube by the simple constitution. Further, pressure can be accumulated in a shorter period of time than in the case of accumulating the pressure discontinuously.

[0067] Further, the above-described summary of the invention does not enumerate all of characteristics necessary for the invention but a sub combination of the group of characteristics can constitute the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0068] The above objects and advantages of the present invention will become more apparent by describing in detail preferred exemplary embodiments thereof with reference to the accompanying drawings, wherein:

[0069]FIG. 1 is a partial perspective view of an ink jet type recording apparatus according to a first embodiment of the invention;

[0070]FIG. 2 is a sectional view of a tube according to the embodiment;

[0071]FIG. 3 illustrates sectional views showing a state of depressing to flatten the tube;

[0072]FIG. 4 is a disassembled perspective view viewing a tube pump according to the embodiment from a skewed lower direction;

[0073]FIG. 5 is a disassembled perspective view viewing the tube pump according to the embodiment from a skewed upper direction;

[0074]FIG. 6 is an outline perspective view of a printer according to a second embodiment of the present invention;

[0075]FIG. 7 is an outline constitution view of an essential portion of the printer according to the embodiment;

[0076]FIG. 8 is a partially disassembled perspective view of a tube pump according to the embodiment;

[0077]FIG. 9 is a partially sectional view of a discharging tube according to the embodiment;

[0078]FIG. 10 is a partially disassembled perspective view of a pressing device according to the embodiment;

[0079]FIG. 11 is a perspective view of a rotating member according to the embodiment;

[0080]FIG. 12 is a front view of the pressing device according to the embodiment;

[0081]FIG. 13 is a plane view of the pressing device according to the embodiment;

[0082]FIG. 14 is a front view of the pressing device according to the embodiment;

[0083]FIG. 15 is a plane view of the pressing device according to the embodiment;

[0084]FIG. 16 is a partially broken plane view of the tube pump according to the embodiment;

[0085]FIG. 17 is a partially broken plane view of the tube pump;

[0086]FIG. 18 is a partially broken plane view of the tube pump according to the embodiment;

[0087]FIG. 19 is an outline constitution view of a tube pump according to a related art; and

[0088]FIG. 20 is an outline constitution view of a tube pump according to a related art.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0089] Although an explanation will be given of the invention through embodiments of the invention as follows, the following embodiments do not limit the invention according to the scope of claims and all of combinations of characteristics to be explained in the embodiments are not necessarily indispensable in resolving means of the invention.

[0090]FIG. 1 is a partial perspective view of an ink jet type recording apparatus 10 according to the first embodiment of the invention. The ink jet type recording apparatus 10 is provided with a feed motor 41 used for feeding a recorded object 11, a recording portion 40 for recording on the fed recorded object 11, and a discharge roller 20 for discharging the recorded object 11 in this order in a feeding direction. The ink jet type recording apparatus 10 is further provided with an ink transporting portion 70 for transporting discharged ink, wiping portion 80 and a drive portion 50.

[0091] The recording portion 40 includes a carriage 42 for mounting an ink cartridge, a recording head 44 provided at a face of the carriage 42 opposed to the recorded object 41 for delivering ink, a shaft hole 46 provided at the carriage 42, a guide shaft 48 inserted into the shaft hole 46 for slidably supporting the carriage 42 in a direction substantially orthogonal to the feeding direction, a timing belt 402, a carriage motor 404, a black ink cartridge 406 and a color ink cartridge 408.

[0092] The black ink cartridge 406 and the color ink cartridge 408 are mounted detachably to an upper portion of the carriage 42 for supplying black ink and color ink to the recording head 44. The recording head 44 includes a delivery port for black ink and a delivery port for color ink as a plurality of delivery ports aligned along the feeding direction of the recorded object 11.

[0093] The ink transporting portion 70 includes capping member 72 arranged at a non-recording region (home position) outside of a recording region (feed path of the recorded object 11) for sealing the delivery ports of the recording head 44, a tube 75 for transporting ink which is ejected from the delivery ports to the capping member 72, a tube pump 76 for transporting ink in the tube 75 from upstream to downstream by elastically deforming a portion of the tube 75, and a waste solution box 79 for accumulating ink transported by the tube pump 76 in this order in a direction of transporting ink. That is, an upstream side of the tube 75 communicates with the capping member 72 and a downstream side of the tube 75 communicates with the waste solution box 79. The waste solution box 79 includes an absorbing member for absorbing an ink waste solution at inside thereof and accumulates the received ink waste solution at inside thereof.

[0094] The wiping portion 80 has an elasticity and arranged at a vicinity of an end portion of the capping member 72 on a side of the recording region. The drive portion 50 drives the feed motor 41 and the carriage motor 404.

[0095] In the above, the carriage motor 404 drives the timing belt 402 so that the carriage 42 is reciprocally moved substantially orthogonal to the feeding direction of the recorded object 11 while being guided by the guide shaft 48. The ink jet type recording apparatus 10 delivers ink from the recording head 44 while reciprocating the carriage 42. The ink jet type recording apparatus 10 carries out recording operation on a total of the recorded object 11 by feeding the recorded object 11 at each scan. The recording head 44 may carry out recording operation in both of a going path and a returning path or may carry out recording operation only in one of the paths.

[0096] When recording operation is not carried out by the ink jet type recording apparatus 10, the carriage 42 moves from the recording region to the non-recording region. When the recording head 44 provided on the carriage 42 is moved right above the capping member 72, the capping member 72 moves up to the side of the carriage 42 and seals a face of the recording head 44 having the delivery ports.

[0097] In the sealed state, the tube pump 76 sucks air at an inner space formed by the recording head 44 and the capping member 72 so that ink is forcibly sucked to discharge from the delivery ports of the recording head 44 to enable to clean a delivery port. The capping member 72 can prevent the delivery ports from being dried by sealing the face of the recording head 44 having the delivery ports. Further, in flushing for making the recording head 44 idly deliver ink drops, the capping member 72 receives the idly delivered ink. The flushing is carried out by applying a drive signal which is not related to recording to the recording-head 44.

[0098] The carriage 42 is firstly separated from the capping member 72 when returning from the non-recording region to the recording region. Further, in accordance with movement of the carriage 42 to the side of the non-recording region, the wiping portion 80 advances onto a movement path of the recording head 44 to wipe ink on a nozzle forming face of the recording head 44.

[0099] In the tube pump of the related ink jet type recording apparatus, a length of a ring-like portion of the tube is adjusted by visual observation after the tube has been arranged in a ring-like shape at inside of the tube pump. Therefore, there is a case in which the length of the ring-like portion of the tube is not adjusted optimally. Further, an upstream portion and a downstream portion of the tube are held in the tube pump respectively by being shifted in a direction intersected with the ring-like portion of the tube. Therefore, there poses a problem that a space for holding the upstream portion and the downstream portion of the tube is enlarged and the tube pump is large-sized.

[0100] Also, the first related tube pump transports ink to the downstream side of the tube by depressing to flatten the tube from the upstream side to the downstream side. Here, there is a case of providing a plurality of the tubes between the capping member and the waste solution box in order to increase an amount of transporting ink.

[0101] Further, there is the tube in which outer peripheries of a plurality of tube main bodies are directly connected with an object of facilitating operation of integrating the tube.

[0102] In this case, when the tube pump depresses to flatten the tube, contiguous tube main bodies are deformed to push each other. Thereby, a load necessary for depressing to flatten a plurality of tube main bodies becomes larger than a load in the case of depressing to flatten a single one of the tube main body multiplied by a number of pieces of the tube main bodies to thereby pose a problem that torque for driving the tube pump is increased and a motor for driving the tube pump becomes large-sized.

[0103]FIG. 2 is a sectional view of the tube 75. FIG. 3 illustrates sectional views showing a state in which the tube 75 is depressed to flatten, FIG. 3A shows a state in which a tube connecting portion 750 is not buckled and FIG. 3B shows a state in which the tube connecting portion 750 is buckled. The tube 75 includes a plurality of tube main bodies 75 a and 75 b each having a flow path and the tube connecting portion 750 for connecting the plurality of tube main bodies 74 a and 74 b separately from each other. The tube connecting portion 750 escapes wall thicknesses of the plurality of tube main bodies when the tube for the tube pump is depressed to flatten.

[0104] The tube connecting portion 750 connects the plurality of tube main bodies 75 a and 75 b substantially at a center in a direction of depressing to flatten the plurality of tube main bodies 75 a and 75 b. As shown in FIG. 2, the tube connecting portion 750 separates the plurality of tube main bodies 75 a and 75 b from each other in a state in which the tube 75 is not depressed to flatten. Further, as shown in FIGS. 3A and 3B, the tube connecting portion 750 makes the plurality of tube main bodies 75 a and 75 b proximate to each other when the tube 75 is depressed to flatten. FIG. 3A shows a state in which the tube connecting portion 750 is contracted and the plurality of tube main bodies 75 a and 75 b become proximate to each other to thereby escape wall thicknesses thereof. FIG. 3B shows a state in which the tube connecting portion 750 is buckled and the plurality of tube main bodies 75 a and 75 b become proximate to each other to thereby escape the wall thicknesses.

[0105] As described above, a load necessary for pressing to flatten the tube becomes smaller than that in the case of directly connecting the outer peripheries of the plurality of tube main bodies. Therefore, the torque for driving the tube pump 76 can be reduced, and the motor for driving the tube pump 76 and therefore, the tube pump 76 can be downsized. Further, the tube pump 76 can be downsized in a range in which the contiguous tube main bodies 75 a and 75 b are not deformed to push each other.

[0106] Further, the tube connecting portion 750 connects the plurality of tube main bodies 75 a and 75 b substantially at the center in a direction of depressing to flatten the plurality of tube main bodies 75 a and 75 b to thereby uniformly depress to flatten the respective tube main bodies 75 a and 75 b.

[0107] In the firs related tube pomp, when the tube is depressed to flatten by a small load, there is a concern that one of the tube main bodies is not sufficiently depressed to flatten. In this case, a flow rate of a total of the tube is reduced because ink at inside of the tube main body is not sufficiently pushed out. However, according to the embodiment, the respective tube main bodies 75 a and 75 b are uniformly depressed to flatten and therefore, the flow rate of the total of the tube 75 is prevented from being reduced owing to the above-described.

[0108] Further, the tube 75 is made to be less difficult to be depressed to flatten by the tube connecting portion 750 by buckling the tube connecting portion 750 when the tube 75 is depressed to flatten.

[0109] The load of depressing to flatten the tube 75 is the load of depressing to flatten one of the plurality of tube main bodies 75 a and 75 b multiplied by the number of pieces of the tube main bodies, that is, multiplied by two. In this case, the tube 75 is sufficiently depressed to flatten such that the load of depressing to flatten the tube 75 is not larger than the load when one of the plurality of tube main bodies 75 a and 75 b is depressed to flatten multiplied substantially by the number of pieces of the tube main bodies, that is, substantially multiplied by two.

[0110] Further, according to the embodiment, a diameter R of one of the two tube main bodies 75 a and 75 b is 4.6 mm, a wall thickness t is 1 mm and a distance d between centers of the two tube main bodies 75 a and 75 b is 5.1 mm. In this case, the tube 75 is sufficiently depressed to flatten even when the load of depressing to flatten the tube 75 is twice as much as the load when one of the tube main bodies 75 a and 75 b is depressed to flatten.

[0111]FIG. 4 is a disassembled perspective view viewing the tube pump 76 according to the embodiment from a skewed lower direction. FIG. 5 is a disassembled perspective view viewing the tube pump 76 from a skewed upper direction. The tube pump 76 includes a pump holder 760 for holding the tube 75, a tube holder 77 for pinching the tube 75 to fix to the pump holder 760, and a tube pump main body 790 driven to rotate by power from outside. Further, the tube holder 77 includes a tube holder main body 770 and a tube holder lid 780. In FIG. 5, the tube 75 and the tube pump main body 790 are omitted for simplicity.

[0112] The pump holder 760 has a substantially cylindrical shape. The pump holder 760 includes a first guide groove 762 and a second guide groove 764 for fixing the tube holder main body 770 to the pump holder 760 and a tube support face 766 for restricting an outer shape of the tube 75 in a shape of a circular arc.

[0113] The tube holder main body 770 includes a notch 772 and a locking claw 779 to be engaged with the tube holder lid 780, a first engaging portion 774 and a second engaging portion 776 to be engaged with the pump holder 760, a tube contact face 777 brought into contact with the tube 75 and a positioning projection 778 for positioning the tube 75.

[0114] The tube contact face 777 is formed to bend along a length direction of the tube 75. The positioning projection 778 is slenderly formed on the tube contact face 777 to be along the length direction of the tube 75 and along the tube connecting portion 750 of the tube 75.

[0115] The tube holder lid 780 includes a projection 782 to be engaged with the notch 772 of the tube holder main body 770, a tube contact face 783 brought into contact with the tube 75, a positioning projection 784 for positioning the tube 75, a shift preventing projection 785 for preventing shift of the tube 75, and a recessed portion 786 for locking the locking claw 779 of the tube holder main body 770.

[0116] The tube contact face 783 is formed to bend along the length direction of the tube 75. The positioning projection 784 is slenderly formed to project on the tube contact face 783 to be along the length direction of the tube 75 and along the tube connecting portion 750 of the tube 75. The shift preventing projections 785 are respectively formed at a portion at which the tube main bodies 75 a and 75 b are brought into contact with each other on the tube contact face 783. Further, the shift preventing projection 785 is slenderly formed in a direction intersecting with the positioning projection 784. Further, although not illustrated, also the tube holder main body 770 is formed with a projection similar to the shift preventing projection 785 on the tube contact face 777.

[0117] The tube pump main body 790 includes a roller 792 rotatably attached to the tube pump main body 790 for depressing to flatten the tube 75 from an inner side of the ring.

[0118] In the above constitution, the tube holder lid 780 and the tube holder main body 770 pinch the tube 75 in a ring-like shape such that the tube 75 becomes a ring-like shape and an upstream side extended portion extended upstream from a ring-like portion of the tube 75 and a downstream side extended portion extended downstream from the ring-like portion of the tube 75 overlap.

[0119] Further, the tube holder lid 780 is fitted together with the tube holder main body 770 by engaging the projection 782 of the tube holder lid 780 to the notch 772 of the tube holder main body 770 and locking the locking claw 779 of the tube holder main body 770 to the recessed portion 786 of the tube holder lid 780. In this case, the upstream side extended portion and the downstream side extended portion of the tube 75 overlapped to each other are held by the tube holder 77 by respectively being brought into contact with the tube contact face 777 and the tube contact face 783.

[0120] Under the state, the respective tube connecting portions 750 of the upstream side extended portion and the downstream side extended portion of the tube 75 overlapped to each other are positioned along the positioning projection 778 of the tube holder main body 770 and the positioning projection 784 of the tube holder lid 780. Thereby, movement of the tube 75 in the diameter direction of the tube 75 is restricted.

[0121] By restricting movement of the tube 75 in the diameter direction, one of the tube main bodies 75 a and 75 b is prevented from being compressed. Thereby, the flow rate of the total of the tube 75 is prevented from being reduced owing to a reduction in a flow path sectional area of one of the tube main bodies 75 a and 75 b.

[0122] Further, the tube 75 is held by the tube holder 77 in a bent state by being pinched between the tube contact face 777 and the tube contact face 783 both of which are bent. Thereby, a resistance between the tube 75 and the tube contact face 777 or the tube contact face 783 becomes larger than that in the case in which the tube 75 is held by the tube holder 77 in a straight state. Thereby, even when the tube 75 is subjected to external force, the tube 75 is difficult to shift from the tube holder 77.

[0123] Further, by forming the shift preventing projection 785 on the tube contact face 783 and forming a similar projection also on the tube contact face 777, the projections constitute a resistance when the tube 75 is moved. Thereby, the upstream side extended portion and the downstream side extended portion of the tube 75 are respectively difficult to shift from the tube holder 77 even when subjected to external force.

[0124] Further, the projections of the shift preventing production 785 and the like are respectively formed at a portion at which the tube main bodies 75 a and 75 b are brought into contact with each other on the tube contact face 777 and the tube contact face 783 and therefore, both of the tube main bodies 75 a and 75 b are difficult to shift from the tube holder 77 even when subjected to external force. Further, one of the tube main bodies 75 a and 75 b is prevented from being shifted from other thereof in the length direction of the tube 75.

[0125] Next, the tube holder 77 is mounted to the pump holder 760 by engaging the first engaging portion 774 and the second engaging portion 776 of the tube holder main body 770 to the first guide groove 762 and the second guide groove 764 of the pump holder 760. In this way, the tube 75 pinched by the tube holder 77 is held by the pump holder 760 to constitute the ring-like shape in a state of overlapping the upstream side extended portion and the downstream side extended portion. Here, a direction of attaching and detaching the tube holder 77 to and from the pump holder 760 is a direction intersecting with the ring of the tube 75.

[0126] Thereby, the upstream side extended portion and the downstream side extended portion of the tube 75 are held by the pump holder 760 at one location. Therefore, a space of holding the upstream portion and the downstream portion is reduced and the pump holder 760 is downsized in comparison with a case of holding the upstream side and the downstream side of the tube 75 respectively at the pump holder 760 by shifting in a direction intersecting with the ring-like portion.

[0127] Further, a length of the ring-like portion of the tube 75 is determined by being held by the tube holder 77 and therefore, the ring-like portion of the tube 75 can be adjusted to a desired length before arranging the tube 75 to be along the inner wall of the pump holder 760. Thereby, operational performance is promoted in comparison with that in the case of adjusting the length of the ring-like portion of the tube 75 while integrating the tube 75 to the pump holder 760.

[0128] Further, according to the embodiment, by integrating the tube 75 to the pump holder 760, the tube 75 is simultaneously positioned to the tube supporting face 766.

[0129] Thereby, operational performance is promoted in comparison with that in the case of positioning the tube 75 to the tube supporting face 766 after integrating the tube 75 to the pump holder 760.

[0130] Further, the direction of attaching and detaching the tube holder to and from the pump holder 760 is a direction intersecting with the ring of the tube 75 and therefore, the tube 75 can be attached and detached to and from the pump holder 760 without operating excessive external force to the tube 75.

[0131] Further, an interval between the tube holder 770 and the tube holder lid 780 when the tube holder 77 is attached to the pump holder 760 is smaller than an outer diameter of the tube 75. Thereby, when the tube holder 77 is attached to the pump holder 760, the tube holder 770 and the tube holder lid 780 fasten the tube 75. Therefore, even when a force of fitting the tube holder main body 770 and the tube holder lid 780 is small, the tube 75 is firmly held by the pump holder 760 along with the tube holder 77.

[0132] Next, when the tube 75 is contained in the pump holder 760, the outer shape of the ring of the tube 75 is restricted to the shape of the circular arc along the tube supporting face 766. By containing the tube pump main body 790 in the ring of the tube 75 under the state, the tube 75 is drawn around the tube pump main body 790.

[0133] When the tube pump main body 790 is rotated by power from outside under the state, the roller 792 successively depresses to flatten one point of the tube 75 from upstream to downstream. Thereby, the tube pump main body 790 transports the ink waste solution at inside of the tube 75 depressed to flatten to downstream. The tube 75 depressed to flatten recovers by an elastic force of the tube 75 per se to produce negative pressure at inside of the tube 75. By conducting the negative pressure to the upstream side of the tube 75, the ink waste solution on the upstream side of the tube 75 is sucked. The tube pump main body 79 transports the ink waste solution on the upstream side of the tube 75 to the waste solution box 79 on the downstream side of the tube 75 by repeating the processes.

[0134] As is apparent from the above-described explanation, according to the tube pump 76 of the embodiment, the length of the ring-like portion of the tube 75 can previously be adjusted before the tube 75 is arranged to be along the inner wall of the pump holder 760. Therefore, the length of the ring-like portion of the tube 75 is made to be easily to adjust optimally.

[0135] Next, the second embodiment of the invention will be explained in reference to FIG. 6 through FIG. 18 as follows.

[0136] As shown in FIG. 6, in a printer 111 as a liquid ejecting apparatus of the embodiment, a platen 113 is installed to a frame 112 thereof and paper P is fed on the platen 113 by a paper feed mechanism, not illustrated. A carriage 115 is supported on the frame 112 movably in a longitudinal direction of the platen 113 via a guide member 116 and reciprocally moved by a carriage motor 117 via a timing belt 118.

[0137] Further, the carriage 115 is mounted with a recording head 120 on a lower side thereof. The recording head 120 is provided with a nozzle delivery port, not illustrated, at a lower face thereof and ink drops are delivered from the nozzle delivery port by driving a piezoelectric element, not illustrated.

[0138] An ink cartridge 121 is detachably mounted on the carriage 115 and ink is supplied from the ink cartridge 121 to the recording head 120. Therefore, printing is carried out by delivering ink from the recording head 120 onto the paper P by driving the piezoelectric element based on printing data.

[0139] A head cleaning mechanism 125 is provided at a non-recording region (home position) at one side portion of the frame 112. As shown in FIG. 6 and FIG. 7, the head cleaning mechanism 125 has a cap holder 126 and a tube pump 128. The cap holder 126 is attached to the frame 112 movably in an up and down direction by a publicly-known lifting mechanism, not illustrated.

[0140] A cap 129 in a shape of a square frame is provided on the cap holder 126. The cap 129 can seal the nozzle delivery port of the recording head 120 by bringing an upper end edge thereof into contact with the recording head 120. Further, as shown in FIG. 7, the cap 129 is fixedly attached with a sponge 131 in a shape of a sheet at a bottom portion thereof. The sponge 131 is opposed to the nozzle delivery port of the recording head 120 at a predetermined interval therebetween in a state of bringing the cap 129 into contact with the recording head 120 for receiving ink delivered from a nozzle of the recording head 120. Further, the cap 129 is formed with a discharge port 132 to penetrate a bottom face thereof.

[0141] The tube pump 128 sucks ink from the recording head 120 by decompressing inside of the cap 129 in a state of sealing the nozzle delivery port of the recording head 120, and discharges ink to a waste ink tank 133 provided at inside of the frame 112.

[0142] In details, as shown in FIG. 8, the tube pump 128 is provided with a casing 135, a discharging tube 136 and a pressing device 137. The casing 135 is formed in a cylindrical shape in a bottomed shape by a resin and is formed with a support hole 139 to penetrate at a center of a bottom face 138 thereof. Further, a portion of a side face of the casing 135 is formed with a notch portion 141 to notch from an upper side to a lower side up to before the bottom face 138. Further, the casing is projected with a groove portion 142 an upper side of which is opened to extend from the notch portion 141 to an outer side in a diameter direction of the casing 135. Further, an inner side of the groove portion 142 of the casing 135 is provided with two of fitting projected portions 143 and 144 extended in an up and down direction and the fitting projected portions 143 and 144 are opposed to each other.

[0143] The discharging tube 136 is a tube formed of a flexible member of silicone rubber or the like, as shown in FIG. 9. The discharging tube 136 has two flexible tubes 146 and 147 according to the embodiment and the flexible tubes 146 and 147 are connected by an connecting portion 148 to integrate. Further, the flexible tubes 146 and 147 are respectively formed with flow paths 146 a and 147 a therein.

[0144] Further, as shown in FIG. 8, according to the discharging tube 136, in a state in which the respective flexible tubes 146 and 147 are aligned in an up and down direction, an upstream side end portion 150 and a downstream side end portion 151 of a flow path middle portion 149 are bundled such that flow directions thereof are directed reverse to each other. As a result, a flow path middle portion 149 draws substantially a shape of a circular arc. Further, the upstream side end portion 150 and the downstream side end portion 151 are bundled by a fastening portion 53 made of a resin formed substantially in a shape of a rectangular parallelepiped to form a bundled portion 152 and in details, the bundled portion 152 is formed by simultaneously inserting the upstream side end portion 150 and the downstream side end portion 151 into an inserting hole 53 a provided at the fastening portion 49. Further, the fastening portion 53 is formed with fitting grooves 54 and 55 to extend in the up and down direction at two side faces thereof opposed to each other.

[0145] Further, as shown in FIG. 7, an upstream side portion 136 a of the discharging tube 136 is connected to the discharge port 132 of the cap 129. Further, a downstream side portion 136 b thereof is connected to the waste ink tank 133.

[0146] Further, as shown in FIG. 8, the discharging tube 136 is attached to the casing 135 by sliding the fastening portion 53 relative to the groove portion 142 of the casing 135 from the upper side to the lower side to thereby engage the engaging grooves 54 and 55 of the fastening portion 53 respectively to the fitting projected portions 143 and 144 of the groove portion 142. Further, as a result, the flow path middle portion 149 of the discharging tube 136 is contained along an inner wall 135 a in a cylindrical shape of the casing 135 and draws a character Ω when viewed in a plane direction.

[0147] As shown in FIG. 10, the pressing device 137 is provided with a rotating member 156, a torsional spring 157, a supporting member 158, a contact member 159 and a retaining piece 160. The rotating member 156 has a center shaft 161 and a circular disk portion 162 integrally formed therewith by a resin. The center shaft 161 is provided with a small diameter portion 163 and a large diameter portion 164 having a diameter larger than that of the small diameter portion 163 to align to dispose on an axis center A shown in FIG. 10 successively from the upper side. At a middle of the large diameter portion 164, the circular disk portion 162 is provided to dispose on the axis center A at a center thereof and orthogonal to the center shaft 161. Further, at a portion of the large diameter portion 164 on a side upper than the circular disk portion 162, there is formed a first fitting face 165 (refer to FIG. 13, FIG. 15) having a shape notched to be flat in a direction of the axis center A. Further, at a portion of the large diameter portion 164 on a side lower than the circular disk portion 162, there is formed a second fitting face 167 having a shape notched from a lower side thereof to a middle thereof in the direction of the axis center A.

[0148] The circular disk portion 162 is provided with an outer diameter smaller than an inner diameter of the casing 135. Further, the circular disk portion 162 is formed with an upper side circular through hole 168 and an upper side rectangular through hole 169 to penetrate along the axis center A direction. Respective sectional shapes of the upper side circular through hole 168 and the upper side rectangular through hole 169 constitute a circular shape and a rectangular shape. Further, as shown in FIG. 11, the circular disk portion 162 is provided with a projected portion 170 at a lower face 162 a thereof. The projected portion 170 has a first projected portion 170 a, a second projected portion 170 b and a third projected portion 170 c provided to align successively from the upper side. The first projected portion 170 a is provided with a shape of a fan centering on the axis center A and having a diameter smaller than that of the circular disk portion 162 and the second projected portion 170 b is provided with the shape of a fan having a diameter smaller than that of the first projected portion 170 a. Further, the third projected portion 170 c is provided such that a sectional shape thereof in a plane direction constitutes substantially a triangular shape.

[0149] Further, in FIG. 11, respective left side faces of the first projected portion 170 a and the second projected portion 170 b and the third projected portion 170 c are flushed with each other to form a contact face 71. Further, in FIG. 11, respective right side faces of the first projected portion 170 a and the second projected portion 170 b are flush with each other. However, respective side faces of the second projected portion 170 b and the third projected portion 170 c are not flush with each other but form a stepped difference portion 172.

[0150] As shown in FIG. 10, the torsional spring 157 is a spring for generating a recovery force against torsion. The torsional spring 157 has a coil portion 173 and two arms 173 a and 173 b formed at end portions of the coil potion 173. An inner diameter of the coil portion 173 is larger than an outer diameter of the large diameter portion 164 of the center shaft 161 of the rotating member 156. The arm 173 a and 173 b are provided to extend in directions orthogonal to the axis center A when the center axis of the coil portion 173 is disposed on the axis center A. Further, the arm 173 a and the arm 173 b are expanded to open by a predetermined angle.

[0151] The supporting member 158 is provided with a through inserting hole 158 a in parallel with the axis center A at a center thereof and provided with an upper side plate 175 and a lower side plate 176 substantially in a shape of a doughnut plate. Further, the respective side plates 76 and 76 are disposed to be orthogonal to the axis center A, connected by a junction portion 177 and integrally formed by a resin.

[0152] The upper side plate 175 is provided with an outer diameter smaller than that of the circular disk portion 162 of the rotating member 156 and provided with an inner diameter larger than an outer diameter of the torsional spring 157. Further, a portion thereof is notched in a shape of a fan along the axis center A direction to form an upper side plate side opening portion 75 a. Further, an upper face of the upper side plate 175 is projected with a first upper side projected portion 78 and a second upper side projected portion 179 in a cylindrical shape. Further, the upper side projected portion 78 is formed in a size pivotably fitted to the upper side circular through hole 168 formed at the rotating member 156. Further, the second upper side projected portion 179 is formed in a size fitted to the upper side rectangular through hole 169 of the rotating member 156 movably in the longitudinal direction of the upper side rectangular through hole 169.

[0153] Further, a penetrated groove 181 is formed to penetrate the upper side plate 175. In details, the penetrated groove 181 is provided at a vicinity of a middle in a diameter direction of the upper side plate 175 along a circumferential direction substantially over a half periphery thereof and provided such that a distance from a center of the upper side plate 175 is increased as proceeding toward an arrow mark D1 direction of FIG. 10.

[0154] The lower side plate 176 is provided with an outer diameter smaller than the outer diameter of the upper side plate 175 and is provided with an inner diameter coinciding with the inner diameter of the upper side plate 175. Further, a portion (not illustrated) of an outer side face of the lower side plate 176 is provided with a shape coinciding with a face 181 a on an inner side of the through penetrated groove 181 of the upper side plate 175 when viewed in a plane direction. Further, the lower side plate 176 is provided with two lower side projected portions (not illustrated) in a cylindrical shape at a lower face thereof. Further, the lower side projected portions are provided at positions overlapping the respective upper side projected portions 178 and 179 when viewed in a plane direction and sizes thereof are sizes similar to those of the respective corresponding upper side projected portions 178 and 179.

[0155] A sectional shape of the junction portion 177 in a direction orthogonal to the axis center A is a shape of a circular arc. Further, the junction portion 177 is formed with a connecting portion side opening portion 177 a in a shape of being notched in a shape of a fan along the axis center A continuously from the upper side plate side opening portion 75 a of the upper side plate 175. An inner wall face 182 of the connecting portion side opening portion 177 a on the right side of FIG. 10 is projected with a locking projected portion 183. Further, the locking projected portion 183 is provided with a longitudinal direction thereof along the axis center A and a lower end portion thereof is not brought into contact with a lower face 184 of the connecting portion side opening portion 177 a. As a result, a stepped difference portion 185 is formed between the locking projected portion 183 and the lower face 184 of the connecting portion side opening portion 177 a. Further, urging unit has the rotating member 156, the torsional spring 157 and the supporting member 158.

[0156] The contact member 159 has a circular cylindrical portion 187 and shaft portions 188 and 189 (refer to FIG. 12) provided at an upper face and a lower face of the circular cylindrical portion 187. Further, respective center axes of the circular cylindrical portion 187 and the shaft portions 188 and 189 are disposed in a shape of the same straight line in parallel with the axis center A. Further, movement of the contact member 159 in the diameter direction of the support member 58 is restricted by fitting the shaft portion 188 on the upper side to the penetrated groove 181 of the upper side plate 175 from the lower side and bringing the shaft portion 189 on the lower side into contact with the outer side face of the lower side plate 176. Further, movement of the contact member 159 to a lower side in the axis center A direction is restricted by bringing a lower face 187 a of the circular cylindrical portion 187 into contact with an upper face 176 a of the lower side plate 176 of the supporting member 158.

[0157] Further, under the state, the contact member 159 is rotatable centering on the center axis of the circular cylindrical portion 187 and at the same time, can freely be moved reciprocally along the penetrated groove 181 between an escape position T disposed at an initial end portion of the penetrated groove 181 in the arrow mark D1 direction of FIG. 10 and an operating position S disposed at a terminal end portion thereof.

[0158] Further, an attaching groove 181 b directed to an outer side in the diameter direction of the upper side plate 175 is formed at the terminal end portion of the penetrated groove 181 of the supporting member 158 in the arrow mark D1 direction of FIG. 10. The attaching groove 181 b is a groove provided for facilitating to integrate the contact member 159 to the supporting member 158. In details, the contact member 159 can easily be integrated to the supporting member 158 by inserting the shaft portion 188 of the contact member 159 to the attaching groove 181 b.

[0159] The retaining piece 160 is formed in a shape of a circular disk a center of which is disposed on the axis center A and which is orthogonal to the axis center A and an outer diameter thereof becomes smaller than that of the lower side plate 176 of the supporting member 158. Further, the retaining piece 160 is formed with a center hole 191 having a shape coinciding with that of the large diameter portion 164 of the rotating member 156 at a center thereof. Therefore, the center hole 191 is formed with a linear portion 191 a coinciding with the second fitting face 167 of the large diameter portion 164. Further, the retaining piece 160 is provided with a lower side circular through hole 92 and a lower side rectangular through hole 193 at a peripheral edge portion thereof. The lower side circular through hole 92 is provided with a size and a shape the same as those of the upper side circular through hole 168. The lower side rectangular through hole 193 is provided with a size and a shape the same as those of the upper side rectangular through hole 169 of the rotating member 156.

[0160] Further, the pressing device 137 having the rotating member 156, the torsional spring 157, the supporting member 158, the contact member 159 and the retaining piece 160 as described above is integrated by firstly outwardly fitting the torsional spring 157 to the center shaft 161 of the rotating member 156 from the lower side. Further, the arm 173 a of the torsional spring 157 is engaged with the stepped difference portion 172 (refer to FIG. 11 and FIG. 12) of the rotating member 156.

[0161] Next, the center shaft 161 of the rotating member 156 is inserted to penetrate into the through ole 158 a provided at the center of the supporting member 158 from the upper side. Further, the supporting member 158 is previously attached with the contact member 159. Further, the projected portion 170 (refer to FIG. 11) of the rotating member 156 is disposed in the upper side plate side opening portion 75 a and the connecting portion side opening portion 177 a of the supporting member 158. Further, the arm 173 a of the torsional spring 157 is engaged with the stepped difference portion 185 of the supporting member 158 (refer to FIG. 12). Thereafter, the first upper side projected portion 78 and the second upper side projected portion 179 of the supporting member 158 are respectively fitted to the upper side circular through hole 168 and the upper side rectangular through hole 169 of the rotating member 156.

[0162] Successively, the center shaft 161 inserted to penetrate the supporting member 158 is inserted to penetrate the center hole 191 of the retaining piece 160. Further, at this occasion, the second fitting face 167 of the center shaft 161 and the linear portion 191 a of the center hole 191 are engaged with each other and therefore, the retaining piece 160 is attached unrotatably to the rotating member 156. Further, the lower side projected portions of the supporting member 158 are respectively fitted to the lower side circular through hole 92 and the lower side rectangular through hole 193 of the retaining piece 160.

[0163] The pressing device 137 is integrated as described above and as shown in FIG. 12, according to the pressing device 137, an angle made by the arms 173 a and 173 b of the torsional spring 157 is more or less reduced to generate a recovering force against torsion at the torsional spring 157. As a result, in a state in which a force is not applied from outside to the pressing device 137, the rotating member 156 and the supporting member 158 are urged by the torsional spring 157 such that the projected portion 1.70 of the rotating member 156 and the locking projected portion 183 of the supporting member 158 are separated from each other.

[0164] Therefore, as shown in FIG. 13, the supporting member 158 is applied with a force of being pivoted in an arrow mark direction shown in FIG. 13 centering on the first upper side projected portion 78 fitted to the upper side circular through hole 168 and the lower side projected portion. As a result, in a state in which no force is applied from outside, the second upper side projected portion 179 and the lower side projected portion of the supporting member 158 are respectively disposed at right corners shown in FIG. 13 of the upper side rectangular through hole 169 and the lower side rectangular through hole 193 (refer to FIG. 10).

[0165] Further, when a force of reducing the angle made by the arms 173 a and 173 b is applied to the pressing device 137 against the recovery force against torsion of the torsional spring 157 as shown in FIG. 14, the supporting member 158 is pivoted in an arrow mark direction shown in FIG. 15 centering on the first upper side projected portion 78 and the lower side projected portion as shown in FIG. 15. Further, the second upper side projected portion 179 and the lower side projected portion of the supporting member 158 are respectively disposed at left corners shown in FIG. 15 of the upper side rectangular through hole 169 and the lower side rectangular through hole 193 (refer to FIG. 10). Further, as shown in FIG. 14, the distance between the projected portion 170 of the rotating member 156 and the locking projected portion 183 of the supporting member 158 is reduced.

[0166] Therefore, in the case in which the contact member 159 attached to the supporting member 158 is disposed at the operating position S (refer to FIG. 10) of the penetrated groove 181, when no force is applied from outside to the contact member 159, as shown in FIG. 12, the contact member 159 is disposed at a position most remote from the axis center A, that is, a first position. Further, when some force is applied from outside to the supporting member 158 as shown in FIG. 14, the contact member 159 is disposed at a position more proximate to the axis center A than the first position, that is, a second position, since the second upper side projected portion 179 and the lower side projected portion of the supporting member 158 are respectively moved to at left corners of the upper side rectangular through hole 169 and the lower side rectangular through hole 193. Further, when the force applied to the supporting member 158 is changed, in accordance with the magnitude of the force, the contact member 159 is disposed at any position between the first position and the second position while being disposed at the operating position S of the penetrated groove 181.

[0167] Further, as shown in FIG. 16, the pressing device 137 constituted as described above is fitted to the casing 135 attached with the discharging tube 136 such that the center shaft 161 of the pressing device 137 is inserted to penetrate the support hole 139 (refer to FIG. 8) of the casing 135. Further, at this occasion, the contact member 159 of the pressing device 137 is brought into contact with the flow path middle portion 149 of the discharging tube 136 from the inner side. Further, the tube pump 128 is finished as described above.

[0168] Next, an explanation will be given of operation of the printer 111 constituted as described above.

[0169] First, an explanation will be given of a case of cleaning the recording head 120 at the printer 111. In such a case, the carriage 115 is moved to the home position and the recording head 120 is covered by the cap 129. Further, as shown in FIG. 16, according to the tube pump 128, the rotating member 156 of the pressing device 137 is rotated in an arrow mark D2 direction (regularly rotating direction) shown in FIG. 16.

[0170] Then, the contact portion 59 supported by the supporting member 158 is applied with a force in a direction reverse to the regularly rotating direction by a friction force generated between the contact member 159 and the flow path middle portion 149 of the discharging tube 136. As a result, the contact member 159 is moved along the penetrated groove 181 of the supporting member 158 to dispose at the operating position S. Further, the contact member 159 presses the flow path middle portion 149 of the discharging tube 136 while being disposed at the operating position S and is rotated in the regularly rotating direction.

[0171] As a result, by depressing to flatten the discharging tube 136 and bringing about a change in the volume at inside of the discharge tube 36, a pressure at the upstream side portion 136 a of the discharging tube 136 becomes lower than a pressure at the downstream side portion 136 b. Further, a pressure at inside of the cap 129 connected to the upstream side portion 136 a of the discharging tube 136 is reduced and ink or air bubbles are sucked from the nozzle opening of the recording head 120.

[0172] Further, at this occasion, the supporting member 158 for supporting the contact member 159 is applied with a reaction force which the contact member 159 receives from the flow path middle portion 149. Further, the larger the applied force, the more the supporting member 158 is moved from the first position (refer to FIG. 12) to the second position (refer to FIG. 14). Particularly, as shown in FIG. 17, since the bundled portion 152 at which the discharging tube 136 is bundled is disposed at a position remote from the center shaft 161, the magnitude of the reaction force applied to the contact member 159 becomes smaller than that at other portion. Therefore, the position of the supporting member 158 becomes proximate to the first position. As a result, also at the bundled portion 152, the discharging tube 136 is depressed to flatten by the contact member 159 by a pertinent pressing force. Further, at the bundled portion 152, the upstream side end portion 150 and the downstream side end portion 151 of the flow path middle portion 149 are simultaneously depressed to flatten by the contact member 159.

[0173] Therefore, the position of the supporting member 158 is changed from the first position to the second position in accordance with the magnitude of the force received from the discharging tube 136 and therefore, when rotated in the regularly rotating direction, a state of depressing to flatten some portion of the discharging tube 136 can always be brought about even when the contact member 159 is disposed at any position in the rotating direction. Further, the upstream side portion 136 a of the discharging tube 136 is prevented from being opened to the downstream side portion 136 b. As a result, by continuously rotating the rotating member 156 in the regularly rotating direction, pressure can be accumulated gradually from first rotation to second rotation, from second rotation to third rotation.

[0174] Further, when the cleaning has been finished, as shown in FIG. 18, according to the tube pump 128, the rotating member 156 of the pressing device 137 is rotated by a predetermined number of times in an arrow mark D3 direction (reversely rotating direction) shown in FIG. 18 by diving unit. Then, the contact member 159 supported by the supporting member 158 is applied with a force in a direction reverse to the reversely rotating direction by the friction force generated between the contact member 159 and the flow path middle portion 149 of the discharging tube 136. As a result, the contact member 159 is moved along the penetrated groove 181 of the supporting member 158 to dispose at the escape position T. Further, at the escape position T, the contact member 159 is lightly brought into contact with the flow path middle portion 149 of the discharging tube 136.

[0175] As a result, the flow path middle portion 149 of the discharging tube 136 is not depressed to flatten and a pressure difference is not brought about in the discharging tube 136. Further, in printing or pause for a long period of time of the printer 111, the printer is left for a long period of time under the state and deformation, a deterioration of durability or the like of the discharging tube 136 is prevented.

[0176] According to the embodiments, the following effects can be achieved.

[0177] (1) According to the embodiment, the flow path middle portion 149 of the discharging tube 136 is arranged at inside of the casing 135 to draw character Ω. Therefore, the discharging tube 136 is not provided with an overlapped portion of the tube formed, for example, when the tube is intersected in an α-like shape. As a result, an extra space in the axis center A direction produced by the overlapped portion needs not to ensure and the tube pump 128 can be downsized.

[0178] (2) According to the embodiment, when the rotating member 156 is regularly rotated, the contact member 159 supported by the supporting member 38 is pressed to the discharging tube 136 by an elastic force by the torsional spring 157 engaged with the supporting member 158. Therefore, the discharging tube 136 is flexibly pressed by the contact member 159. As a result, when regularly rotated, the flow path middle portion 149 including also the bundled portion 152 are uniformly depressed to flatten. Further, at the bundled portion 152, the upstream side end portion 150 and the downstream side end portion 151 can simultaneously be depressed to flatten and even when the flow path middle portion 149 of the discharging tube 136 has the Ω-like shape and is not provided with the overlapped portion, some portion of the discharging tube 136 can always be depressed to flatten by the single contact member. Therefore, pressure can be accumulated continuously at inside of the discharging tube 136 by a simple constitution. Further, pressure can be accumulated in a shorter period of time than in the case of accumulating pressure discontinuously.

[0179] (3) According to the embodiment, the casing 135 is formed in the cylindrical shape and the urging unit has three members of the rotating member 156, the torsional spring 157 and the supporting member 158. Therefore, the constitution of the urging unit can be simplified.

[0180] (4) According to the embodiment, the supporting member 158 is provided with the penetrated groove 181 and the contact member 159 is made movable to the operating position S for pressing the discharging tube 136 by the contact member 159 and the escape position T of being brought lightly into contact with the discharging tube 136 in accordance with a rotational direction of the rotating member 156. Therefore, the supporting member 158 can serve as a member constituting the urging member and a member for making the contact member 159 movable to the operating position S and the escape position T and the structure of the tube pump 128 can be simplified.

[0181] (5) According to the embodiment, the discharging tube 136 has two flexible tubes 146 and 147. Therefore, a sucking function of the tube pump 128 can be increased more than that in the case of a single piece of the flexible tube. Further, even when the discharging tube 136 has two flexible tubes 146 and 147, since the flexible tubes 146 and 147 are not provided with an overlapped portion in the axis center A direction, only a space in the axis center A direction of two pieces of the flexible tubes may be provided and therefore, the tube pump 128 can be downsized.

[0182] (6) According to the embodiment, the flexible tubes 146 and 147 are connected by the connecting portion 148 to constitute one aggregation and therefore, the flexible tubes 146 and 147 are easy to deal with and operation of integrating the discharging tube 136 to the tube pump 128 is facilitated.

[0183] (7) According to the embodiment, only one of the contact member 159 is provided. Therefore, the structure of the tube pump 128 can be simplified. Further, the upstream side end portion 150 and the downstream side end portion 151 can simultaneously be depressed to flatten by only a single one of the contact member 159 and even when the flow path middle portion 149 of the discharging tube 136 is not provided with the overlapped portion, some portion of the discharging tube 136 can always be depressed to flatten by the single contact member 159. As a result, pressure can continuously be accumulated at inside of the discharging tube 136.

[0184] Further, the above embodiment may be modified as follows.

[0185] Although according to the embodiment, the torsional spring 157 is used as elastic member, the other elasticity member, for example, rubber, tension spring, leaf spring or the like may be used.

[0186] Although according to the embodiment, the discharging tube 136 has two flexible tubes 146 and 147, the discharging tube 136 may be constituted only by a single piece of the flexible tube. Further, the discharging tube 136 may be constituted by three pieces or more of the flexible tubes.

[0187] Although according to the embodiment, the flexible tubes 146 and 147 constituting the discharging tube 136 are connected by the connecting portion 148, the flexible tubes 146 and 147 may not be connected to each other.

[0188] Although according to the embodiment, the tube pump 128 is provided with only a single one of the contact member 159, the tube pump 128 may be provided with two pieces or more thereof.

[0189] Although according to the embodiment, an explanation has been given such that the tube pump 128 is an apparatus used for cleaning the printer 111, the tube pump 128 may be used for use other than the printer 111.

[0190] Although according to the first and the second embodiments, an explanation has been given of the printer for delivering ink (printing apparatus including facsimile, copier or the like) as a liquid ejecting apparatus, the embodiment may be a liquid ejecting apparatus for ejecting other liquid. For example, the embodiment may be a liquid ejecting apparatus for ejecting a liquid of an electrode member, a colorant or the like used for fabricating liquid crystal display, EL display, FED (face electroluminescence display) or the like, a liquid ejecting apparatus for ejecting a biological organic substance used for fabricating a biochip, or a sample ejecting apparatus as a precision pipet.

[0191] Although an explanation has been given of the invention by using the embodiments as described above, the technical range of the invention is not limited to the range described in the embodiments. The embodiments can variously be modified or improved. It is apparent from the description of the scope of claims that the modified or improved mode in this way can also be included in the technical range of the invention. 

What is claimed is:
 1. A tube for a tube pump, comprising: a plurality of tube bodies, each including a flow path; and a tube connecting portion, connecting the tube bodies separately from each other so as to escape wall thicknesses of the tube bodies in a state that the tube is depressed to flatten.
 2. The tube as set forth in claim 1, wherein the tube is depressed to flatten by a load given by multiplying a load for depressing a single tube body of the tube bodies to flatten by substantially a number of the tube bodies of the tube.
 3. The tube as set forth in claim 1, wherein the tube includes at least two tube bodies connected by the tube connecting portion; and wherein a diameter of each of the tube bodies is 4.6 mm, a wall thickness thereof is 1 mm, and a distance between centers of adjacent tube bodies of the at least two tube bodies is 5.1 mm.
 4. The tube as set forth in claim 1, wherein the tube connecting portion separates the tube bodies from each other in a state that the tube is not depressed to flatten; and wherein the tube makes the tube bodies proximate to each other in a state that the tube is depressed to flatten.
 5. The tube as set forth in claim 4, wherein the tube connecting portion is buckled so as to make the tube bodies proximate to each other when the tube is depressed to flatten.
 6. The tube as set forth in claim 1, wherein the tube connecting portion connects the tube bodies substantially at a center of the tube bodies in a direction of depressing the tube bodies to flatten.
 7. A tube pump, comprising: a tube, drawn out in a shape of a ring; a tube pump body, including a roller, and rotating the roller for depressing to flatten the tube from an inner side of the ring; a pump holder, having substantially a cylindrical shape, and containing the tube pump body and the tube therein; and a tube holder, detachably mounted on the pump holder, and holding the tube in the shape of the ring as a ring portion by overlapping an upstream side portion extended upstream from the ring portion of the tube and a downstream side portion extended downstream from the ring portion of the tube.
 8. The tube pump as set forth in claim 7, wherein the tube holder is detachably mounted on the pump holder in a direction intersecting with the ring portion of the tube.
 9. The tube pump as set forth in claim 7, wherein the tube includes a plurality of tube bodies; and wherein the tube holder includes a positioning projection projected along a longitudinal direction of the tube bodies for positioning the tube bodies.
 10. The tube pump as set forth in claim 7, wherein the tube holder holds the tube in a state of bending the tube.
 11. The tube pump as set forth in claim 7, wherein the tube holder includes a tube holder body and a tube holder lid; wherein the tube holder body and the tube holder lid holds the tube at a clearance therebetween; and wherein the clearance is smaller than an outer diameter of the tube in a sate that the tube holder is attached to the pump holder.
 12. A tube pump, comprising: a tube; a tube pump body, including a roller, and rotating the roller for depressing to flatten the tube; and a pump holder, having substantially a cylindrical shape, and containing the tube pump body and the tube therein, wherein the tube has a curve portion, an upstream side portion extended upstream from the curve portion, and a downstream side portion extended downstream from the curve portion; and wherein the tube is drawn out from the tube pump body so as to overlap the upstream side portion and the downstream side portion being parallel each other.
 13. A tube pump, comprising a tube; a casing, containing a flow path middle portion of the tube; and a pressing member, pressing the flow path middle portion against an inner wall of the casing, wherein the pressing member includes: a contact member, facing to the casing through the tube; and an urging member, urging the contact member to the tube by an elastic force.
 14. The tube pump as set forth in claim 13, wherein the inner wall of the casing is formed in a cylindrical shape; wherein the urging member includes: a rotating member, rotated with a center of the inner wall as an axis center; a supporting member, supported on the rotating member so that a distance of the contact member from the axis center can be changed, and supporting the contact member; and an elastic member, disposed between the rotating member and the supporting member, and urging the supporting member by the elastic force such that the contact member is separated from the axis center.
 15. The tube pump as set forth in claim 13, wherein the flow path middle portion is contained along the inner wall of the casing so as to draw in a Q shape; and wherein the tube has a bundled portion in which an upstream side end portion and a downstream side end portion of the flow path middle portion are overlapped in a state that directions of liquid flow in the upstream side end portion and the downstream side end portion are reverse to each other.
 16. The tube pump as set forth in claim 15, wherein the supporting member is supported on the rotating member such that a position of the contact member can be changed between a first position and a second position; wherein the first position is capable of pressing the bundled portion so that the upstream side end portion and the downstream side end portion are simultaneously depressed to flatten; and wherein the second position is capable of depressing to flatten the flow path middle portion between the upstream side end portion and the downstream side end portion.
 17. The tube pump as set forth in claim 13, wherein the tube includes a plurality of tubes.
 18. The tube pump as set forth in claim 17, wherein the tubes has a tube connecting portion which connects adjacent tubes of the tubes.
 19. The tube pump as set forth in claim 13, wherein only a single one of the contact member is provided on the supporting member.
 20. A liquid ejecting apparatus, comprising: a tube pump, including: a tube; a casing, containing a flow path middle portion of the tube; and a pressing member, pressing the flow path middle portion against an inner wall of the casing, wherein the pressing member includes: a contact member, facing to the casing through the tube; and an urging member, urging the contact member to the tube by an elastic force.
 21. The liquid ejecting apparatus as set forth in claim 20, wherein the flow path middle portion is contained along the inner wall of the casing so as to draw in a Ω shape; and wherein the tube has a bundled portion in which an upstream side end portion and a downstream side end portion of the flow path middle portion are overlapped in a state that directions of liquid flow in the upstream side end portion and the downstream side end portion are reverse to each other. 